LOW Light FOCUS?? How do you do it?

[Kristy]

I'm having a heck of a time getting my Tamron to focus in low light. Even in a studio set-up, there sometimes isn't enough ambient light to get auto focus to lock... I keep switching to manual, but it takes longer and honestly I don't trust my eyes as well as the AF.

Is it my lens? It doesn't focus much all all in the dark, like on Halloween for Trick-or-Treating kids... Manual Focus 99% of the time and I can't see what I'm focusing on either so it's a crap shoot of getting a sharp shot.

Just wondering what you more experienced people do. Is that the difference between Tamron 28-75 and Cannon's comparable "L"??

Thanks for taking the time to consider my question. :)

Happy Day!

[In2Photos]

Can't compare it to the L but I experienced the same thing last night. Even with the focus assist on the flash I still had trouble. Incidentily I used my 85 1.8 for the first time last night and didn't have the same trouble. In my case the XT doesn't help matters either.

[Curtis N]

As if you don't already have enough reasons to get a good flash unit...

A flash unit with AF assist light will enable you to literally focus in the dark (within a reasonable distance). The 20D has a custom function to prevent the flash from firing if you don't want it.

With that same custom function enabled, you could pop-up the built-in flash and let its AF assist work, though it might annoy your subjects.

[Kristy]

As if you don't already have enough reasons to get a good flash unit...

A flash unit with AF assist light will enable you to literally focus in the dark (within a reasonable distance). The 20D has a custom function to prevent the flash from firing if you don't want it.

With that same custom function enabled, you could pop-up the built-in flash and let its AF assist work, though it might annoy your subjects.

Okay, I have the 580 ex and have used it very little... it's pretty new still. I didn't see the AF assist beam emitting from it, although I have my camera's custom function turned on to AF Assit Beam Emits...

Now what?? Is there a setting inside the flash unit that needs to be turned on, or am I doing something wrong. I had my camera set at Manual and Flash says ETTl with compensation set at Zero for lack of knowledge. I printed the flash bible and read it a couple months ago, but that was a complete blur...

perhaps I need to read it 30 more times and see if something sinks in... It's like another language... mabye I have a mental block to learning flash... too much stuff in my brain now to focus on anything more...

[Moppie]

Okay, I have the 580 ex and have used it very little... it's pretty new still. I didn't see the AF assist beam emitting from it, although I have my camera's custom function turned on to AF Assit Beam Emits...



Make sure your in single shot focus, it won't emitt in the other modes.
Also note that it if only a small correction is needed, and there is still a bit of ambiant light, it might flash only long enough for the camera to see it, but not for you to notice it.

[Kristy]

Make sure your in single shot focus, it won't emitt in the other modes.
Also note that it if only a small correction is needed, and there is still a bit of ambiant light, it might flash only long enough for the camera to see it, but not for you to notice it.


Okay so the FLASH won't emit or the AF assist beam won't emit? The flash was flashing just fine, but the AF assist beam was not there, or if it was, my
Lens' AF feature was unable to lock...

I'm wondering if the problem is my lens, the AF Assist Beam, or some user error... How DO you focus in low light? Manually or does the camera do it?

[Moppie]

The flash's AF assist will only emit if the camera is one shot focus :)

[Kristy]

Allright... Let's see... my camera was set to AI Servo, so that's why I wasn't getting the beam... I'll have to try it again and see what happens.. It's not dark now, but I can see the beam is emitting...

Do you think that is my problem? Or is this lens not capeable of focusing in low light? I keep wondering if it's almost time to upgrade my lens.

[In2Photos]

Allright... Let's see... my camera was set to AI Servo, so that's why I wasn't getting the beam... I'll have to try it again and see what happens.. It's not dark now, but I can see the beam is emitting...

Do you think that is my problem? Or is this lens not capeable of focusing in low light? I keep wondering if it's almost time to upgrade my lens.
Kristy the Tamron is not a good lens for focusing in low light. The AF assist beam helps but not always.

[René Damkot]

The lens will probabely focus fine with the AF assist beam...
It is possible to set a CFn to prevent the flash from fireing. (and also possible to set a CFn to prevent the AF assist light; in fact it's the same CFn, and it also can (dis)able the built in flash/AF assist light. It's all in the manual...

[Curtis N]

Okay, I have the 580 ex...I assumed otherwise since it's not in your signature. ;)

I think you'll be fine with the AF assist light working. Last night I used that same lens, same camera and Sigma flash (which has an AF assist light but not as good as the 580EX) and it locked focus without hesitation on trick-or-treaters in near total darkness.

[rhys]

I use the AF assist on my 420EX or it is possible to make the XT use its strobe flash from the on-body flash to help AF. I tend to focus manually at night using my eye. Normally it comes out fine.

[Moppie]

Iv used the modeling light to help focus, if you hit at he same time as you try and lock focus it should work. It worked for me, untill I read the manual to turned back to one shot focus, and used the AF assist light instead :)

[codex0]

Often with low light, I try to find a particularly high-contrast point at about the right distance and focus on that (such as an LED on stage equipment if I'm shooting a really dimly-lit band).
Often when the focus starts really hunting I just flip into manual focus mode and "best guess," which often works pretty well. I focus in and out, noting where it gets noticeably out of focus, then try to end up as close to between the two out of focus areas as possible. This method is not incredibly accurate, but it's better than nothing. :)

[Jim G]

Make sure your in single shot focus, it won't emitt in the other modes.




Actually it will... AI Focus will emit the AF assist beams, you are correct for AI Servo though.

[Moppie]

Actually it will... AI Focus will emit the AF assist beams, you are correct for AI Servo though.

Ahhh, so it will, thanks for the correction.

[Tsmith]

I don't think the AF assist lamp will work if the flash is adjusted at a bounce angle.

[Moppie]

I don't think the AF assist lamp will work if the flash is adjusted at a bounce angle.

My 550 will, I assume a 580 should as well :)
Anyone know what hapens if you take the flash off camera with the canon off shoe cord 2?

[Curtis N]

Anyone know what hapens if you take the flash off camera with the canon off shoe cord 2?AF assist still works fine, at least with my Sigma flash. With a cord that connects all the wires, I don't think the flash even knows it's not mounted on the camera.

When using a bracket, it's important to make sure the camera and flash are lined up so the AF assist lights hit their target.

[Tsmith]

My 550 will, I assume a 580 should as well :)
Anyone know what hapens if you take the flash off camera with the canon off shoe cord 2?

Yea you correct as I just verified it with my 430EX.

add this: try setting the the various focus points and see if the flash will omit the AF assist lamp each time. I had seen where this was an issue sometimes.

[Moppie]

add this: try setting the the various focus points and see if the flash will omit the AF assist lamp each time. I had seen where this was an issue sometimes.


Well Ill be.
550 on the 30D, it dosn't emitt when the top or bottom point are selected, bu when one of the side points is selected it emitts a wide horizontal pattern, rather than the small vertical pattern it emitts useing the centre point.
You learn something everyday.
I wonder how the 580 behaves on the 30D?

[blackshadow]

The Canon 24-70L works pretty well with low light AF.

[queenbee288]

The Tamron is a great little lens for the price but it does have trouble focusing in low light.

[Kristy]

Wow! Thanks everyone for your input... It's always nice to get opinions from other people. I'll have to play around with the AF assist feature this weekend and see what it does for me. The Canon 24-70 is Huge on my WISH list, but not for at least 9 months or so.... :)

Happy Day!

[rhys]

I don't think the AF assist lamp will work if the flash is adjusted at a bounce angle.

I think it does. I've seen many wedding photographers with the flash aimed up and using the AF assist to focus while keeping the flash from illuminating the couple.